Acoustic ceiling board with improved aesthetics

ABSTRACT

Described herein are acoustical panels, comprising: a substrate; a non-woven veil having an airflow resistance of greater than 45 mks rayls, comprising: from about 20 wt. % to about 60 wt. % glass fibers; from about 40 wt. % to about 80 wt. % of a filler; and from about 110 dry g/m 2  to about 135 dry g/m 2  of a coating. Methods of making and using the panels are also described.

FIELD OF THE DISCLOSURE

The present disclosure relates to building panels having improved visualand acoustical performance, and more particularly to ceiling boards thatmaintain or exceed visual performance with less paint.

BACKGROUND

Building panels are used in a variety of applications inside a buildingstructure to create aesthetically and acoustically pleasing roomenvironments. The building panels may be formed into panels that can beapplied to the walls, ceilings (in some instances forming a suspendedceiling system), and canopies. In some applications, building panelshave suitable aesthetics; however, such panels may not provide properair flow or acoustical properties. In order for a panel to functioneffectively as a ceiling panel, it must be able to provide anaesthetically pleasing appearance while also providing sufficient airflow to enable appropriate acoustical properties.

Thus, there remains a need for building panels that provide acombination of aesthetics and acceptable acoustical performance.Embodiments of the present invention are directed to meeting theseneeds.

SUMMARY

In some embodiments, the present invention provides an acoustical panel,comprising: a substrate; a non-woven veil having an airflow resistanceof greater than 45 mks rayls, comprising: glass fibers; and a filler;and from about 110 dry g/m² to about 135 dry g/m² of a coating.

In some embodiments, the present invention provides an acoustical panel,comprising: a substrate; a non-woven veil having an airflow resistanceof greater than about 50 mks rayls, comprising: glass fibers; and afiller; and from about 110 dry g/m² to about 135 dry g/m² of a coating.

In some embodiments, the present invention provides an acoustical panel,comprising: a substrate comprising an inorganic fiber; and a coatednon-woven veil having an airflow resistance of less than about 300 mksrayls.

Some embodiments provide a coated non-woven veil comprising: a non-wovenveil having an airflow resistance of greater than 45 mks rayls,comprising: glass fibers; and a filler; and from about 110 dry g/m² toabout 135 dry g/m² of a coating comprising: a binder; particles; and acarrier; wherein the coated non-woven veil has an airflow resistance ofabout 300 mks rayls or less.

Some embodiments provide a coated non-woven veil comprising: a non-wovenveil having an airflow resistance of greater than about 50 mks rayls,comprising: glass fibers; and a filler; and from about 110 dry g/m² toabout 135 dry g/m² of a coating comprising: a binder; particles; and acarrier; wherein the coated non-woven veil has an airflow resistance ofabout 300 mks rayls or less.

Some embodiments provide a method of improving the aesthetics of anacoustical panel, comprising: affixing to a substrate, a non-woven veilhaving an airflow resistance of greater than 45 mks rayls comprising:from about 20 wt. % to about 60 wt. % glass fibers; and from about 40wt. % to about 80 wt. % of a filler; applying to the non-woven veil,from about 155 wet g/m² to about 200 wet g/m² of a coating comprising: abinder; particles having a d₅₀ of from about 50 microns to about 300microns; and a carrier; and drying the coated non-woven veil. In someembodiments the coated non-woven veil is dried for a time and at atemperature effective to provide from about 110 dry g/m² to about 135dry g/m² of the coating.

Some embodiments provide a method of improving the aesthetics of anacoustical panel, comprising: affixing to a substrate, a non-woven veilhaving an airflow resistance of greater than about 50 mks raylscomprising: from about 20 wt. % to about 60 wt. % glass fibers; and fromabout 40 wt. % to about 80 wt. % of a filler; applying to the non-wovenveil, from about 155 wet g/m² to about 200 wet g/m² of a coatingcomprising: a binder; particles having a d₅₀ of from about 50 microns toabout 300 microns; and a carrier; and drying the coated non-woven veil.In some embodiments the coated non-woven veil is dried for a time and ata temperature effective to provide from about 110 dry g/m² to about 135dry g/m² of the coating.

In other embodiments, the present invention provides a method ofimproving the aesthetics of an acoustical panel, comprising: applying acoating comprising a binder; particles; and a carrier to a non-wovenveil having an airflow resistance of greater than 45 mks rayls in anamount effective to provide from about 110 dry g/m² to about 135 dryg/m² of the coating; and affixing said coated non-woven veil to asubstrate; wherein the coated non-woven veil has an airflow resistanceof about 300 mks rayls or less.

In other embodiments, the present invention provides a method ofimproving the aesthetics of an acoustical panel, comprising: applying acoating comprising a binder; particles; and a carrier to a non-wovenveil having an airflow resistance of greater than about 50 mks rayls inan amount effective to provide from about 110 dry g/m² to about 135 dryg/m² of the coating; and affixing said coated non-woven veil to asubstrate; wherein the coated non-woven veil has an airflow resistanceof about 300 mks rayls or less.

DETAILED DESCRIPTION

The features and benefits of the present invention are illustrated anddescribed herein by reference to exemplary embodiments. This descriptionof exemplary embodiments is intended to be read in connection with theaccompanying drawings, which are to be considered part of the entirewritten description. In the description of embodiments disclosed herein,any reference to direction or orientation is merely intended forconvenience of description and is not intended in any way to limit thescope of the present invention.

As used herein, terms such as “attached,” “affixed,” “connected,”“coupled,” “interconnected,” and the like refer to a relationshipwherein structures are secured or attached to one another eitherdirectly or indirectly through intervening structures, as well as bothmovable or rigid attachments or relationships, unless expresslydescribed otherwise. Accordingly, the disclosure is not limited to suchexemplary embodiments illustrating certain combinations of features thatmay exist alone or in combination with other features.

In some embodiments, the terms “board” and “panel” are usedinterchangeably.

As used herein, the term “about” is intended to encompass values thatare within 10% of the value which the term modifies.

In some embodiments, the present invention provides an acoustical panel,comprising: a substrate; a non-woven veil having an airflow resistanceof greater than about 50 mks rayls, comprising: glass fibers; and afiller; and from about 110 dry g/m² to about 135 dry g/m² of a coating.

In some embodiments, the present invention includes an acoustical panelhaving multiple layers. In some embodiments, the layers include asubstrate, a veil, and a coating. In some embodiments, the layersinclude a substrate, an adhesive layer, a veil, and a coating.

In some embodiments, the substrate comprises a first major side and asecond major side, the first major side being opposite to the secondmajor side. In some embodiments, the first major side may be a frontside which is facing towards a building space or room environment andthe second major side may be a rear side which is concealed from viewwhen the substrate is mounted.

Some embodiments provide that the substrate further includes peripherallateral sides extending all the way around a core which collectivelydefine a perimeter edge of the substrate that in turn defines a lengthand width. In some embodiments, the perimeter edge may have a square orrectangular edge profile, but other suitable edge profiles may beprovided.

In some embodiments, the veil comprises an outward side and an inwardside, the outward side being opposite to the inward side. In someembodiments, the outward side may be a front side which is facingtowards a building space or room environment and the inward side may bea rear side which is concealed from view when the substrate is mounted.

In some embodiments, the first major side of the substrate is joined tothe inward side of the veil with an adhesive. In some embodiments theadhesive may be a pressure sensitive adhesive, a hot melt adhesive, or acombination thereof. In some embodiments, the adhesive comprises a hotmelt adhesive. In some embodiments, the adhesive comprises a pressuresensitive adhesive. In some embodiments, the adhesive comprisespolyvinyl acetate. In some embodiments, the adhesive comprises ethylenevinyl-acetate (EVA).

In some embodiments, the coating may be applied to outward side of theveil. In some embodiments, the coating may be applied to the outwardside of the veil before or after the veil is adhered to the first majorside of the substrate. In some embodiments, the outward side of the veilto which a coating is applied is referred to as the “outward surface”.

In some embodiments the substrate may be formed from an inorganic fiber.Some embodiments provide that the fiber may be selected from mineralwool, slag wool, rock wool, fiberglass, and a combination of two or morethereof. In some embodiments, the substrate may be formed from anorganic fiber, such as cellulosic fibers selected from wood fibers,paper fibers, or cotton linters. In some embodiments, the inorganicfiber and/or the organic fiber may come from a recycled source.

In some embodiments, the inorganic fiber is added to the coating toimprove sound absorption and to provide hardness and durability. In someembodiments, mineral wool may be used as the inorganic fiber due to itsfire-resistance and because it does not serve as a food source forvermin, molds or bacteria. In other embodiments, granular or nodulatedwool may be convenient because it is pourable and free-running—nodulatedwool is also formed from mineral wool fibers in the pulp mixer. In someembodiments, nodulated wool is in the form of small, porous balls ofirregular shape, such as the size of a pea or larger, often having adiameter in the range of about 0.1 mm to about 6 mm.

In some embodiments, the amount of the fibrous filler used is at leastabout 65 wt. % based on the dry solids weight of the substrate, but canalso vary from about 65 wt. % to about 90% wt. % by weight based on thedry solids weight of the substrate. In some embodiments, the fiberlength may range from about 1 mm to about 4 mm.

In some embodiments, the substrate may include non-fibrous fillers, suchas kaolin clay, calcium carbonate, limestone, silica, vermiculite, ballclay or bentonite, talc, mica, gypsum, perlite, titanium dioxide, sand,barium sulfate, dolomite, polymers, wollastonite, calcite, aluminumtrihydrate, pigments, zinc oxide, and zinc sulfate. In some embodimentsthe substrate may include from about 0 wt. % to about 25 wt. % of thenon-fibrous filler. In another embodiment, the substrate may compriseexpanded perlite in an amount ranging from about 0.1 wt. % to about 50wt. % based on the weight of the substrate.

In some embodiments, the substrate may comprise a binder. Someembodiments provide that the binder may be selected from granularstarches, polymers, and a combination thereof. In some embodiments thesubstrate may include between about 1 wt. % to about 35 wt. % of binder.In some embodiments the substrate may include between about 3 wt. % toabout 10 wt. % of binder. In some embodiments the substrate may includebetween about 4 wt. % to about 6 wt. % of binder.

The granular starches may include pearl cornstarch, wheat starch, andpotato starch. In some embodiments, the polymers may be produced fromone or more of the following monomers vinyl acetate, vinyl propionate,vinyl butyrate, ethylene, vinyl chloride, vinylidine chloride, vinylfluoride, vinylidene fluoride, ethyl acrylate, methyl acrylate, propylacrylate, butyl acrylate, ethyl methacrylate, methyl methacrylate, butylmethacrylate, hydroxyethyl methylacrylate, styrene, butadiene, epoxy,melamine. In some embodiments, the polymers may include polyurethanes,polyesters, polyethers, polystyrene, natural and modified naturalpolymers, polyvinyl chloride, polyvinyl alcohol, polyvinyl acetate,polymethyl methacrylate, and other acrylate or vinyl polymers. In someembodiments, the polyurethanes are derived from a di or poly-functionalisocyanate compound and a di or poly-functional hydroxyl-compound. Insome embodiments, the polyesters are derived from a di orpoly-functional hydroxyl compound and a di or poly-functional carboxylicacid compound or anhydride compound.

In some embodiments, the substrate may further include additionaladditives such as dispersants, flocculants, defoaming agents,fungicides, biocides, and a combination thereof.

In some embodiments, the substrates may be formed via a conventionalwet-felting process and then sanded to have a thickness in the range ofabout one-half inch to about 1 inch. Specifically, in some embodiments,the substrate may be prepared by mixing together the aforementionedingredients with an amount of water necessary to provide slurryconsistency in conventional mixing and holding equipment. In someembodiments, the ingredients may be mixed together using a high-shearmixer. High mixing speeds may be used to create the high-shearconditions that degrade non-woven fabric to a large degree by separationof the individual fibers. In other embodiments, the high shear mixingdegrades mineral wool by breaking it down into shorter fibers even whenno or few nodules are present, resulting in a smooth coating beingformed.

In some embodiments, the substrate may be prepared by air-lay ordirect-lay or other methods known in the art for preparing substrates asdescribed herein.

In some embodiments, the acoustical performance properties of a panelare enhanced by perforation (pin punching), wheel abrading, embossing oreroding the facing surface of the board. Without these performanceenhancing features, conventional coated acoustical panels may not beable to attain the desired acoustical performance characteristics.

In some embodiments the non-woven veil may include fibers, filler,binder, or a combination thereof. In some embodiments, the non-wovenveil may having a thickness ranging from about 0.2 mm to about 0.5 mm;alternatively a thickness of about 0.4 mm. In some embodiments, thenon-woven veil has a basis weight of from about 100 g/m² to about 150g/m²; alternatively the non-woven veil has a basis weight of about 125g/m².

In some embodiments the fibers may include glass fibers, wood fibers,and a combination thereof. In some embodiments, the fibers may have anaspect ratio from about 10:1 to about 1:10. In some embodiments thefibers may include glass fibers, wood fibers, and a combination thereof.In some embodiments, the fibers may have an aspect ratio from about 5:1to about 1:5. In some embodiments the fibers may include glass fibers,wood fibers, and a combination thereof. In some embodiments, the fibersmay have an aspect ratio from about 4:1 to about 1:2. In someembodiments, the fibers may be 3-9 mm in length.

In some embodiments the binder comprises an ingredient selected frompolyvinyl alcohol, starch, a cellulosic resin, a polyamide, apolyacrylamide, a polyester, a polyolefin, a water soluble vegetablegum, urea-formaldehyde, melamine-formaldehyde, amelamine-phenol-formaldehyde copolymer, an acrylic copolymer, and acombination of two or more thereof. In some embodiments, the polyolefinsinclude polypropylene and polyethylene.

In some embodiments, the non-woven veil comprises a filler selectedfrom: calcium carbonate, aluminum trihydrate (ATH), magnesium hydroxide,dolomite, dolomitic limestone, and combinations thereof. In anotherembodiment, the filler may also include nitrogen-phosphorous based flameretardants, such as intumescent nitrogen-phosphorous compounds, organicnitrogen-phosphorous compounds, inorganic nitrogen-phosphorouscompounds, melamine based products such as melamine-formaldehyde,melamine-polyphosphate, melamine cyanurate, melamine-phosphate,melamine-phenol-formaldehyde copolymers, acrylic copolymers, and bromineand chlorine halogenated fillers and/or resins optionally combined withantimony trioxide or antimony pentoxide synergists.

In some embodiments, the non-woven veil may further comprise a thickeneror a whitener. Some embodiments provide that the thickener preventsparticle settling and provides resistance to shear or elongation ratestriation markings that may arise under processing conditions. Accordingto one embodiment, thickeners may be present in an amount of about 0.1wt. % to about 5 wt. % based on the solid binder content. In someembodiment, thickener may include a polyurethane copolymer, hydroxyethylcellulose, a polyacrylamide, or a pH dependent thickeners, such aspolyacrylates.

In some embodiments, the filler will be substantially spherical andrange in size from about 0.1 to about 600 microns. In some embodiments,the filler will range in size from about 1 micron to about 500 microns.In some embodiments, the filler will range in size from about 10 micronsto about 400 microns. In some embodiments, the filler will range in sizefrom about 50 microns to about 300 microns. In some embodiments, thefiller will range in size from about 200 microns to about 450 microns.In some embodiments, the filler comprises from about 35% to about 90% byweight of the veil composition on a dry solids basis.

According to one embodiment of the present invention, the filleroccupies volume in the non-woven veil that would be otherwise occupiedby fiber or binder. According to another embodiment of the presentinvention, the filler enlarges voids already present between the fiberand/or binder in the non-woven veil. In some embodiments, the presenceof filler may allow for more air to flow through the non-woven veil ofthe present invention when compared to a non-woven veil that containsless filler (but more fiber and/or binder) than the non-woven veils ofthe present invention. Thus, in some embodiments, the addition of fillerthroughout the non-woven veil facilitates airflow through the acousticalpanel. In some embodiments, the addition of filler to the non-woven veilcreates a greater number of air-passageways through the non-woven veiland/or enlarges the air-passageways that would otherwise be presentwithout the addition of filler. In some embodiments, the increasedairflow through the non-woven veil enhances the acoustical performance.

In some embodiments, the addition of filler will result in an air flowresistance of greater than 45 mks rayls for the uncoated non-woven veil.In some embodiments, the addition of filler will result in an air flowresistance of greater than about 50 mks rayls for the uncoated non-wovenveil. In some embodiments, the addition of filler will result in an airflow resistance of from about 50 mks rayls to about 150 mks rayls forthe uncoated non-woven veil. In some embodiments, the addition of fillerwill result in an air flow resistance of from about 50 mks rayls toabout 75 mks rayls for the uncoated non-woven veil. In some embodiments,the addition of filler will result in an air flow resistance of fromabout 51 mks rayls to about 56 mks rayls for the uncoated non-wovenveil. In some embodiments, the addition of filler will result in an airflow resistance of from 52 mks rayls to 53 mks rayls for the uncoatednon-woven veil. In some embodiments, the addition of filler will resultin an air flow resistance of about 52 mks rayls for the uncoatednon-woven veil. In some embodiments, a non-woven veil exhibiting thislevel of airflow resistance will allow sound to pass through thematerial at a rate especially desirable for using the non-woven veil asan acoustical facing for a sound absorbing panel.

In some embodiments, the airflow resistance of coated veils is measuredafter the coated veil is peeled from the finished product.

In some embodiments, the non-woven veil may be formed by mixing togetherbinder and filler with a liquid carrier—such as hot water—followed bythe addition of dispersed fibers and other additional ingredients—suchas an anionic polyacrylamide, dispersant, defoamer, and biocide.

In some embodiments the binder may be present in an amount ranging fromabout 0.1 wt. % to about 30 wt. % based on the weight of the non-wovenveil. In some embodiments the binder may be present in an amount rangingfrom about 1 wt. % to about 20 wt. % based on the weight of thenon-woven veil. In some embodiments the binder may be present in anamount ranging from about 5 wt. % to about 15 wt. % based on the weightof the non-woven veil.

In some embodiments the non-woven fiber may be present in an amountranging from about 20 wt. % to about 60 wt. % based on the weight of thenon-woven veil. In some embodiments the non-woven fiber may be presentin an amount ranging from about 25 wt. % to about 50 wt. % based on theweight of the non-woven veil.

In some embodiments the filler may be present in an amount ranging fromabout 40 wt. % to about 80 wt. % based on the weight of the non-wovenveil. In some embodiments the filler may be present in an amount rangingfrom about 50 wt. % to about 75 wt. % based on the weight of thenon-woven veil. In some embodiments, the filler is present in the amountof about 70 wt. % of the non-woven veil.

Randomly dispersed fiber orientation and filler throughout the non-wovenveil is preferred for two reasons: (1) the resulting non-woven veil iscapable of installation in any direction without preferential markingsand (2) the particles are generally distributed throughout the non-wovenveil volume in a generally homogenous fashion, thereby maximizing theamount of even air flow through the voids created or enlarged by theaddition of the filler.

In some embodiments, the coating composition of the present inventionmay include a binder, particles and a carrier.

Some embodiments provide that the particles may have sufficient size toimpart physical texture to the outward side (or surface) of thenon-woven veil and/or aesthetic properties to the outward, or top,surface of the non-woven veil. In some embodiments, the particles willhave a size sufficient to impart desired aesthetic properties whiletending not to completely plug or seal the openings within the non-wovenveil or substrate.

In some embodiments, particles may include calcium carbonate, dolomite,dolomitic limestone, kaolin clay, mica, talc, silica, titanium dioxide,barium sulfate, perlite, gypsum, wollastonite, calcite, aluminumtrihydrate, zinc oxide, zinc sulfate, polymers, other various pigmentsand combinations thereof.

In some embodiments, the particles will be substantially spherical andhave a d₅₀ ranging from about 0.1 to about 600 microns. In someembodiments, the particles have a d₅₀ ranging from about 1 micron toabout 500 microns. In some embodiments, the particles have a d₅₀ rangingfrom about 10 microns to about 400 microns. In some embodiments, theparticles have a d₅₀ ranging from about 50 microns to about 300 microns.In some embodiments, the particles have a d₅₀ ranging from about 200microns to about 450 microns. In some embodiments, the particles have ad₅₀ ranging from about 10 microns to about 150 microns.

In some embodiments, the particles are homogeneously distributedthroughout the coating.

In some embodiments, the particles may constitute from about 1 wt. % toabout 99 wt. % of the coating composition on a dry solids basis. In someembodiments, the particles may constitute from about 15 wt. % to about95 wt. % of the coating composition on a dry solids basis. In someembodiments, the particles may constitute from about 35 wt. % to about90 wt. % of the coating composition on a dry solids basis.

In other embodiments, the coating may further comprise dispersants,defoamers and viscosity modifying agents—such as thickening agents orthinning agents. In some embodiments, the coating comprises tetrasodiumpyrophosphate as a dispersing agent. In another embodiment, the coatingmay comprise hydroxyethyl cellulose as a thickener.

In some embodiments the binders which can be used with the presentinvention include epoxies, urethanes, melamine, polyesters, acryliclatex, natural and modified natural polymers, and vinyl polymers. Insome embodiments, the polymers can include one or more of the followingmonomers vinyl acetate, vinyl propionate, vinyl butyrate, ethylene,vinyl chloride, vinylidine chloride, vinyl fluoride, vinylidenefluoride, ethyl acrylate, methyl acrylate, propyl acrylate, butylacrylate, ethyl methacrylate, methyl methacrylate, butyl methacrylate,hydroxyethyl methylacrylate, styrene, butadiene, urethane, epoxy,melamine, and an ester. Examples of natural and modified naturalpolymers are protein and carbohydrate polymers such as starch. In someembodiments, the binders may include polyurethanes, polyesters,polyolefins, polyvinyl chloride, and combinations thereof.

In some embodiments, the binder concentration of the coating may be inthe range of from about 2 wt. % to about 30% wt. % based on the totalweight of the coating. In some embodiments, the aqueous carrier may bewater. In some embodiments, the coating may further comprise adispersing agent that is present in the coating from about 0.5 wt. % toabout 2.5% wt. % based on the total weight of the coating. In someembodiments, the coating may further comprise a thickener that may bepresent in an amount ranging from about 0.2 wt. % to about 2.5 wt. %based on the total weight of the coating.

In those embodiments wherein the particles include pigments, the binderconcentration is such that the pigment to binder ratio is in the rangefrom about 0.5:1 to about 90:1 on a dry solids basis. In someembodiments, the particles include pigments. In those embodimentswherein the particles include pigments, the binder concentration is suchthat the pigment to binder ratio is in the range from about 5:1 to about30:1 on a dry solids basis. In some embodiments, the particles includepigments.

In some embodiments, the coating composition exhibits a viscosity in therange of from 5 cP to about 50,000 cP as measured on a Brookfieldviscometer at 10 rpm. In some embodiments, the coating composition has aviscosity of up to about 10,000 cps. In another embodiment, the coatingcomposition exhibits a viscosity in the range of from about 1100 cP toabout 5000 cP as measured on a Brookfield viscometer at 10 rpm. Unlessotherwise indicated, viscosity values refer to measurements taken atabout 25° C.

In some embodiments, the present invention provides a coated non-wovenveil comprising: a non-woven veil having an airflow resistance ofgreater than about 50 mks rayls, comprising: glass fibers; and a filler;and a coating comprising: a binder; particles; and a carrier; whereinthe coated non-woven veil has an airflow resistance of about 300 mksrayls or less. In some embodiments, the coated non-woven veil comprisesfrom about 110 dry g/m² to about 135 dry g/m² of the coating.

In certain embodiments, wherein a particular type of coating is beingused and a particular type of substrate is being used, it may bedesirable to include a coated non-woven veil having an airflowresistance of less than 600 mks rayls. It is preferred, however, thatthe coated non-woven veil has an airflow resistance of less than 500 mksrayls; even more preferred less than 375 Inks rayls; and still furtherpreferred less than 325 inks rayls.

Other embodiments provide a method of improving the aesthetics of anacoustical panel, comprising: applying a coating comprising a binder;particles; and a carrier to a non-woven veil having an airflowresistance of greater than about 50 mks rayls in an amount effective toprovide from about 110 dry g/m² to about 135 dry g/m² of the coating;and affixing said coated non-woven veil to a substrate; wherein thecoated non-woven veil has an airflow resistance of 300 mks rayls orless.

In some embodiments, a mineral fiber substrate is prepared via welt feltmethod. In some embodiments, the substrate is sanded to a desiredthickness. In some embodiments, the substrate is sanded to a thicknessof from about 10 mm to about 30 mm. In some embodiments, the substrateis sanded to a thickness of about 20 mm. In some embodiments, thesubstrate is laminated with an uncoated non-woven veil between heatednip rolls using a pressure sensitive adhesive. In some embodiments, thelaminated substrate is then sprayed with a coating comprising a binder,particles and a carrier. In some embodiments, the coated substrate isthen dried by exposure to heat.

Other embodiments provide a method of improving the aesthetics of anacoustical panel, comprising: affixing to a substrate, a non-woven veilhaving an airflow resistance of greater than about 50 mks raylscomprising: from about 20 wt. % to about 60 wt. % glass fibers; and fromabout 40 wt. % to about 80 wt. % of a filler; applying to the non-wovenveil, from about 155 wet g/m² to about 200 wet g/m² of a coatingcomprising: a binder; particles having a d₅₀ of from about 50 microns toabout 300 microns; and a carrier; and drying the coated non-woven veil.

In some embodiments the coated non-woven veil is dried for a time and ata temperature effective to provide from about 110 dry g/m² to about 135dry g/m² of the coating. In some embodiments, the coated non-woven veilis dried at room temperature. In some embodiments, the coated non-wovenveil is dried at a temperature of from about 40° C. to about 150° C. Insome embodiments, the coated non-woven veil is dried at a temperature offrom about 75° C. to about 125° C. In some embodiments, the coatednon-woven veil is dried at a temperature of from about 100° C. to about110° C. In some embodiments, the coated non-woven veil is dried at atemperature of about 105° C.

In some embodiments the coated non-woven veil is dried for about 10seconds to about 30 minutes. In some embodiments the coated non-wovenveil is dried for about 20 seconds to about 15 minutes. In someembodiments the coated non-woven veil is dried for about 30 seconds toabout 5 minutes. In some embodiments the coated non-woven veil is driedfor about 45 seconds to about 2 minutes. In some embodiments the coatednon-woven veil is dried for about 1 minute. In some embodiments thecoated non-woven veil is dried at a temperature of 105° C. for about 1minute.

Further embodiments provide a method of improving the aesthetics of anacoustical panel, comprising: affixing to a substrate, a non-woven veilhaving an airflow resistance of greater than about 50 mks raylscomprising: from about 20 wt. % to about 60 wt. % glass fibers; an fromabout 40 wt. % to about 80 wt. % of a filler; applying to the non-wovenveil a coating comprising: a binder; particles having a d₅₀ of fromabout 50 microns to about 300 microns; and a carrier, in an amounteffective to provide from about 110 dry g/m² to about 135 dry g/m² ofthe coating; and drying the coated non-woven veil.

In some embodiments, a coating described herein is applied to anon-woven veil prior to the non-woven veil being affixed to a substrate.

In some embodiments, the coating composition of the present inventioncan be applied in the form of atomized droplets to the outward surfaceof the veil. In some embodiments, the coating can be applied by spray,mist, fogs, clouds, or aerosol. In one embodiment, the coating may beapplied by spray using a high volume low pressure (HVLP) spray gun thatreduces the amount of clogging in the pore of the veil.

In one embodiment, the coating composition may be fed into a pressuretank that is fluidly coupled with an HVLP spray gun. The fluid tip orfluid nozzle used with the HVLP spray gun has an opening that issufficiently large to allow the filler particles to pass there throughwithout clogging the nozzle or spray gun. The coating is atomized by thespray gun and applied under pressure to the substrate. The HVLP spraygun provides a lower exit velocity to the coating composition thangenerally is provided by other air atomizing application methods,thereby minimizing bounce-back of the coating from the substrate andtending to generate larger droplets distributed in a more narrowlydefined pattern. The HVLP spray apparatus tends to generate adiscontinuous finish that exhibits a coarse texture and preserves thedesired acoustical characteristics of the non-woven veil.

In some embodiments, the coating composition can be applied with theHVLP spray gun to the non-woven veil to form a single coat or layer thatis then allowed to dry or is dried under heated conditions. In otherembodiments, additional coats or layers of the coating composition canbe applied on top of the first coat with a drying step conducted betweeneach application step. In one embodiment, a finish coating may beapplied over the coating layers containing the larger filler material.

Previously, difficulties arose when coating a substrate or a non-wovenveil for the purpose of enhancing cosmetic appearance. Specifically, apigmented coating may be applied to reduce or eliminate the appearanceof small black holes that exist on the outward side of the non-wovenveil. In some embodiments, the appearance of black holes—sometimesreferred to as salt and pepper coloring—correlates with the hiding powerof the non-woven veil. As the hiding power decreases, the morepronounced the appearance of salt and pepper coloring. Previously,pigmented coatings were applied to the outward face of the non-wovenveil in an effort to minimize the amount of salt and pepper coloring.However, as a greater amount of coating is required to minimize oreliminate the salt and pepper coloring, the resulting non-woven veilexhibits sub-par air flow because the applied coating has clogged thevoids and/or channels in the non-woven veil. Thus, previous attempts toenhance the aesthetics of non-woven veils by surface coating resulted inan offsetting detrimental impact on the sound absorption properties ofthe ceiling panel.

Some embodiments provide that the addition of filler within and throughthe non-woven veil reduce the amount of coating needed to eliminate orreduce the salt and pepper coloring. Specifically, filler embeddedwithin and throughout the non-woven veil reduces the visibility of theblack holes on the outward face of the veil. Thus, the filler embeddedwithin the non-woven veil does not detrimentally impact air flow, whilealso creating an unexpected benefit of reducing the amount of coatingrequired to reduce or eliminate the salt and pepper coloring on theoutward side of the veil. In some embodiments the presence of fillerwithin and throughout the non-woven veil allows for a discontinuouscoating to be applied to the outward surface of the veil. In someembodiments, the non-woven veil is coated with from about 110 dry g/m²to about 135 dry g/m². In some embodiments, the non-woven veil is coatedwith from about 115 dry g/m² to about 130 dry g/m². In some embodiments,the non-woven veil is coated with from about 115 dry g/m² to about 125dry g/m². In some embodiments, the non-woven veil is coated with about120 dry g/m². In some embodiments, the non-woven veil is coated with 118dry g/m².

In some embodiments, the acoustic ceiling panel may be formed into aplurality of configurations as desired for a given application soundabsorption and aesthetic needs, including for example, withoutlimitation, polygonal, square, ellipsoidal, circle, hexagon, trapezoid,etc., and with various side profiles including flat, convex, concave,and combinations thereof. Accordingly, the invention is not limited bythe shape of the acoustical substrate.

Some embodiments of the present invention provide a non-woven veil thatdemonstrates a hiding power value of greater than 75%. Some embodimentsof the present invention provide a non-woven veil that demonstrates ahiding power value of greater than 80%. Other embodiments provide anon-woven veil that demonstrates a hiding power value of greater than85%. Further embodiments provide a non-woven veil that demonstrates ahiding power value of greater than 90%. Still further embodimentsprovide a non-woven veil that demonstrates a hiding power value ofgreater than 95%. While other embodiments provide a non-woven veil thatdemonstrates a hiding power value of greater than 98%.

The hiding power of a non-woven veil can be measured by placing thescrim on an Opacity Test Chart, such as the Opacity Chart Form N2A fromthe Leneta Company. The Opacity Chart includes both a white section anda black section over which the lightness of the scrim can be measured.Hiding power can be determined by dividing the lightness value of theblack section by the lightness value of the white section.

Some embodiments provide an acoustical panel, comprising: a substrate; anon-woven veil that demonstrates a hiding power value of greater than75%, comprising: from about 20 wt. % to about 60 wt. % glass fibers; andfrom about 40 wt. % to about 80 wt. % of a filler; and from about 110dry g/m² to about 135 dry g/m² of a coating.

Other embodiments provide a coated non-woven veil comprising: anon-woven veil that demonstrates a hiding power value of greater than75%, comprising: from about 20 wt. % to about 60 wt. % glass fibers; andfrom about 40 wt. % to about 80 wt. % of a filler; and a coatingcomprising: a binder; particles; and a carrier; wherein the coatednon-woven veil has an airflow resistance of about 300 mks rayls or less.

Still further embodiments provide a method of improving the aestheticsof an acoustical panel, comprising: affixing to a substrate, a non-wovenveil that demonstrates a hiding power value of greater than 75%,comprising: from about 20 wt. % to about 60 wt. % glass fibers; and fromabout 40 wt. % to about 80 wt. % of a filler; applying to the non-wovenveil a coating comprising: a binder; particles having a d₅₀ of fromabout 50 microns to about 300 microns; and a carrier, in an amounteffective to provide from about 110 dry g/m² to about 135 dry g/m² ofthe coating; and drying the coated non-woven veil.

The invention will be described in greater detail by way of specificexamples. The following examples are offered for illustrative purposesand are not intended to limit the invention in any manner.

EXAMPLES Example 1

The acoustical panels used to generate the data described in Table 1(below) may be prepared according to the following process. A mineralfiber substrate is prepared via wet felt method. The substrate is sandedto a desired thickness. The substrate is then laminated with an aluminumtrihydrate filled uncoated non-woven veil between heated nip rolls usinga pressure sensitive adhesive. The laminated substrate is then sprayedwith a coating comprising a binder, particles and a carrier. The coatedsubstrate is then dried by exposure to heat.

Example 2

The airflow resistance and light reflectance of coated non-woven veilsaccording to some embodiments of the present invention and comparativenon-woven veils are evaluated. Airflow resistance is measured accordingto ASTM C-522 “Standard Test Method for Airflow Resistance of AcousticalMaterials”. Light Reflectance is determined using the X-Rite Model 964Spectrophotometer, using illuminant type A with the 10 deg observer andwith the 21.5 mm target window. Eight individual measurements areaveraged for each reported value.

The results of these evaluations are described below in Table 1.

TABLE 1 Uncoated Coated Veil Veil Air Flow Coating Air Flow LightResistance Density Resistance Reflectance Example (mks rayls) (dry g/m²)(mks rayls) (%) Ex. I 53 118 245 >85 Ex. II 53 128 300 >85 Comp. Ex. I45 197 323 >85 Comp. Ex. II 45 217 411 >85 Comp. Ex. III 40 236 118 <85

The data described in Table 1 (above) demonstrates that the inventivecombination of a non-woven veil having an airflow resistance (uncoated)of greater than 45 mks rayls, and particular amounts of a coatingcomprising a binder and particles; provides a coated non-woven veil thatdelivers the desired aesthetics (light reflectance) and acousticalperformance (airflow resistance). The data described in Table 1 alsodemonstrates that the comparative combinations of non-woven veils and acoating are not able to provide the desired combination of aestheticsand acoustical performance.

It is intended that any patents, patent applications or printedpublications, including books, mentioned in this patent document behereby incorporated by reference in their entirety.

As those skilled in the art will appreciate, numerous changes andmodifications may be made to the embodiments described herein, withoutdeparting from the spirit of the invention. It is intended that all suchvariations fall within the scope of the invention.

The invention claimed is:
 1. An acoustical panel, comprising: asubstrate; a non-woven veil having an airflow resistance of greater than45 mks rayls, comprising: from about 20 wt. % to about 60 wt. % glassfibers; and from about 40 wt. % to about 80 wt. % of a filler; and fromabout 110 dry g/m² to about 135 dry g/m² of a coating.
 2. The panel ofclaim 1, wherein the non-woven veil demonstrates a hiding power value ofgreater than 75%.
 3. The panel of claim 1, wherein the coated non-wovenveil has an airflow resistance of about 300 mks rayls or less.
 4. Thepanel of claim 1, wherein the filler comprises aluminum trihydrate. 5.The panel of claim 1, comprising about 120 dry g/m² of the coating. 6.The panel of claim 1, wherein the coating is not continuous.
 7. Thepanel of claim 1, wherein the coating comprises a binder and particles.8. The panel of claim 7, wherein the particles have a d₅₀ of from about50 microns to about 300 microns.
 9. The panel of claim 1, wherein thenon-woven veil is affixed to the substrate using an adhesive.
 10. Thepanel of claim 9, wherein the adhesive comprises a pressure sensitiveadhesive.
 11. The panel of claim 1, wherein the non-woven veil has athickness of from about 0.2 mm to about 0.5 mm.
 12. The panel of claim1, wherein the substrate is substantially free of punch holes, wheelabrasions, embossing or erosion.
 13. A coated non-woven veil comprising:a non-woven veil having an airflow resistance of greater than 45 mksrayls, comprising: from about 20 wt. % to about 60 wt. % glass fibers;and from about 40 wt. % to about 80 wt. % of a filler; and a coatingcomprising: a binder; particles; and a carrier; wherein the coatednon-woven veil has an airflow resistance of about 300 mks rayls or less.14. The veil of claim 13, comprising from about 110 dry g/m² to about135 dry g/m² of the coating.
 15. The veil of claim 13, wherein thecarrier is an aqueous carrier.
 16. The veil of claim 13, wherein thebinder is selected from a natural polymer, a modified natural polymer, asynthetic polymer and a combination of two or more thereof.
 17. The veilof claim 13, wherein the particles comprise a material selected fromcalcium carbonate, dolomite, titanium dioxide, barium sulfate, clay,mica, limestone, silica, talc, perlite, gypsum, wollastonite, calcite,aluminum trihydrate, zinc, a polymer, a pigment and a combination of twoor more thereof.
 18. The veil of claim 17, wherein the particles have ad₅₀ of from about 50 microns to about 300 microns.
 19. A method ofimproving the aesthetics of an acoustical panel, comprising: affixing toa substrate, a non-woven veil having an airflow resistance of greaterthan 45 mks rayls comprising: from about 20 wt. % to about 60 wt. %glass fibers; and from about 40 wt. % to about 80 wt. % of a filler;applying to the non-woven veil a coating comprising: a binder; particleshaving a d₅₀ of from about 50 microns to about 300 microns; and acarrier, in an amount effective to provide from about 110 dry g/m² toabout 135 dry g/m² of the coating; and drying the coated non-woven veil.20. The method of claim 19, wherein the non-woven veil is affixed to thesubstrate by lamination using an adhesive.